String Obfuscator
TextObfuscate text by replacing middle characters with asterisks for emails, phones and credit cards to protect sensitive data in logs and screenshots.
About String Obfuscator
When taking demo screenshots, writing docs, or sharing logs, sensitive values like emails, phone numbers, and card numbers must be masked — yet you often want to keep a few leading and trailing characters for recognition. This tool masks strings locally in your browser: you set how many characters to keep at the start and end, and the middle is replaced with a custom symbol (asterisk by default). Built-in email, phone, and card presets are one click away. Nothing is sent or stored; the original data never leaves your device. Tip: Bookmark this tool for quick access whenever you need text processing. All processing happens locally in your browser — no data upload, so feel free to paste private content.
How to Use
- Open the String Obfuscator tool page
- Enter or paste your data into the input area
- View the real-time results and use the copy button to get the output
Use Cases
- Screenshot redaction — Turn a phone number into 138****5678 before capturing, hiding the real digits.
- Doc examples — Show card format in API docs, keeping the first and last four for reference.
- Sharing logs — Mask the middle of emails or tokens before pasting into a forum for help.
- Support tickets — Partially mask user accounts in tickets to balance recognition and privacy.
- Quick presets — Apply common keep-rules instantly with the phone and card presets.
- Mask test data — Obfuscate real-looking test data in seed scripts so they are safe to commit to shared repos.
- Redact CI output — Mask secrets or personal data in CI pipeline logs before sharing build output for debugging.
FAQ
Can masked text be reversed?
No. Masking permanently replaces the middle characters with symbols and is irreversible, so keep a copy of the original.
What if the kept counts exceed the length?
When the kept start and end characters cover the whole string, there is no middle to mask, and the tool returns the input unchanged.
Can I change the asterisk?
Yes. The mask character is customizable — use # or • to match your document style.
Does it mask emails intelligently?
It masks by character position and does not parse email structure. To normalize email format, use our Email Normalizer.
Does it handle CJK or emoji correctly?
It works per character; regular CJK masks fine, but some multi-codepoint emoji may split, so prefer plain-text identifiers.
Any browser compatibility requirements?
This tool works in all modern browsers (Chrome, Firefox, Edge, Safari). No plugins or extensions required.
Can I use it offline?
After initial load, most features work offline. The core logic runs entirely in your browser with no network dependency.
Comments
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